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91.
Toshio Mizutani Ken-ichi Nakamura Mutsuo Enomoto Masuhiro Sakata Shigeo Yamada 《Neuropathology》1998,18(1):80-90
A neuropathological study on 1540 consecutive autopsy brains ranging from 60 to 107 years of age revealed the following points. (1) Of the of the demented cases of the plaque-predominant type, 93% were complicated with multiple tiny cortical infarcts. They showed a tendency for dementia to develop before or after the appearance or worsening of a systemic disorder such as cardiovascular disease, respiratory infection and cancer. However, there was no case showing Alzheimer-type dementia (ATD). (2) The plaque-predominant type might be an extreme condition of brain aging in terms of senile plaques (SP). It is likely that although the pathological appearance of SP alone is not responsible for dementia, its coexistence with multiple cortical infarcts could be the cause of dementia. Therefore, this type should be distinguished from ATD. (3) Primary hippocampal degeneration could also be an extreme condition of brain aging in terms of neurofibrillary tangles. This condition was different pathologically from the hippocampal lesion in ATD. (4) Several characteristics of old-old and oldest-old patients were clarified. 相似文献
92.
Hidemi Kaname Toshio Yoshihara Yuji Yaku Tetsuo Ishii 《Medical Electron Microscopy》1993,26(2):99-104
Primary squamous cell carcinoma of the submandibular gland is a rare tumor. In this report, the histological and ultrastructural
features of a case of primary squamous cell carcinoma arising in the left submandibular gland is presented. Light microscopically,
the tumor consisted of well differentiated keratinizing squamous cell nests. Ultrastructurally, the tumor cells were oval
or spindle-shaped, and several tumor cells had intracytoplasmic desmosome-like structures, resembling intercellular desmosomes.
The majority of the tumor cells contained a large number of intermediate filaments (tonofilaments). Intercellular desmosomes
were well developed. No secretory granules were found. These ultrastructural features may enable us to distinguish primary
squamous cell carcinoma from mucoepidermoid carcinoma which is often misdiagnosed as squamous cell carcinoma. 相似文献
93.
The effect of halothane and enflurane on tracheal tone were studied in 21 patients during the induction of anesthesia. Endotracheal tube cuff pressure was used to measure tracheal tone. Anesthesia, maintained by nitrous oxide 70% in oxygen, was supplimented with succinylcholine drip infusion to immobilize the patient. Ventilation was controlled by a Volume-preset ventilator. In the halothane group, the initial cuff pressure was 14.8 ± 1.3 (mean ± SE) cmH2O but 10min after 0.15mg/kg of pancuronium injection, it increased to 21.7 ± 2.3cmH2O (control). Ten min after inhalation of 0.75% of halothane, cuff pressure decreased to 14.7 ± 2.3cmH2O (34 ± 11% decrease from the control value). In the enflurane group, the initial cuff pressure was 17.6 ± 1.8cmH2O and it increased to 21.0 ± 1.7cmH2O (control) 10min after pancuronium injection. Ten min after 1.7% of enflurane inhalation, cuff pressure decreased to 17.1 ± 2.3cmH2O (23.9 ± 6% decrease from the control value). Halothane and enflurane produced similar tracheal dilatation in healthy individuals.(Yasuda I, Irimada M, Hirano T et al.: Tracheal dilatation by halothane and enflurane in man. J Anesth 2: 46–49, 1988) 相似文献
94.
Naoji Amano Saburo Yagishita Susumu Yokoi Yoji Itoh Jun Kinoshita Toshio Mizutani Takeshi Matsuishi 《Acta neuropathologica》1992,84(1):15-23
Summary This report presents a variant of Gerstmann-Sträussler syndrome (GSS). A 53-year-old female had developed slowly progressive dementia and atactic gait since the age of 45. No myoclonic jerks and periodic synchronous discharges were observed throughout the illness. The neuropathological study revealed that many amyloid plaques and widespread Alzheimer's neurofibrillary tangles (NFTs) appeared in the cerebral cortex. Characteristically, the plaques reacted with anti-prion protein and none of them reacted with anti- protein, and they were made of many components, including amyloid cores, macrophages laden with lipid granules and/or degenerated neurites. Neuropil threads were seen mainly in amyloid plaques. Moreover, plaques appeared which were confluent and laminar in arrangement in the fifth and sixth cortical layers and had a close relationship to the neuronal loss. There was no spongiform change in the cerebral cortex or cerebellum. The cerebellum was almost intact except for a few amyloid plaques. Ultrastructurally, some of the plaques simulated kuru plaques and others had many degenerated neurites possessing paired helical filaments and other accumulated organelles. GSS has been proposed to include cases with progressive ataxia, dementia and massive multifocal plaques in the brain with or without cerebral spongiform changes. The case presented here is a very peculiar case of GSS. Recently, similar cases have been reported in some large families, diagnosed as familial Alzheimer's disease. These cases may be a telencephalic form with numerous NFTs of GSS. 相似文献
95.
A 34-year-old male presented with central diabetes insipidus accompanied by upbeat nystagmus and cerebellar ataxia. The patient without family history of above began to walk at the age of 2 years. Polyposia and polyuria were noted at the age of about 4 years. Dysbasia developed at the age of about 7 years. From the age of 30, lalopathy appeared together with various clinical symptoms including cataracts, disturbed intelligence, upbeat nystagmus, abnormal ocular movements, ataxic speech, cerebellar ataxia and reduction of the muscle tone of the limbs, and hypotonic polyuria. Abnormal laboratory findings included square wave jerks, upbeat nystagmus, and "bow tie" nystagmus by EOG, atrophy of the cerebellum and the brainstem by CT, a slight prolongation of the P300 latency, and a central diabetes insipidus pattern by water deprivation test and Carter-Robbins tests. There have been occasional reports of diabetes insipidus complicated by cerebellar ataxia, but in no earlier reports has diabetes insipidus been concurrent with abnormal ocular movements such as upbeat nystagmus. A degenerative disease primarily of the posterior lobe of the hypophysis, hypothalamus, cerebellum, and brainstem was suspected. 相似文献
96.
Ichiro Ikegaki Yoshio Suzuki Shin-ichi Satoh Toshio Asano Masato Shibuya Kenichiro Sugita 《Naunyn-Schmiedeberg's archives of pharmacology》1989,340(4):431-436
Summary The effects of calcitonin gene-related peptide (CGRP) on canine cerebral arteries and on vertebral blood flow were investigated in-vivo and in-vitro and the findings compared with the effects of vasoactive intestinal peptide (VIP) and substance P. Administration of CGRP into the vertebral artery caused a dose-dependent and long-lasting increase in blood flow. The in-vivo vasodilatory effects of substance P and VIP were short-lasting. CGRP (0.1 to 100 nmol/l) elicited a concentration-dependent relaxation of the isolated middle cerebral and basilar arteries when the tissues were precontracted by exposure to prostaglandin F2 (PGF2). This effect was not antagonized by propranolol, atropine, tetrodotoxin, (N-Ac-Tyr1, D-Phe2)-growth hormone-releasing factor(1–29)-NH2 or (D-Pro2, D-Trp7,9) substance P. CGRP also reduced concentration-dependently the contraction of cerebral arteries induced by KCl or 9,11-epithio-11,12-metano-thromboxane A2 (STXA2). Mechanical removal of the endothelium did not abolish the vasodilatory response to CGRP. In PGF2-contracted canine cerebral arteries, VIP (0.1 to 100 nmol/l) was less potent a vasodilator than CGRP. At low concentrations (0.01 to 1 nmol/l) substance P elicited a rapid and short-lasting relaxation, and in the absence of endothelium this relaxation disappeared. These findings are clear evidence that CGRP modulates vascular tone. 相似文献
97.
Transient induction of single GST-P positive hepatocytes by DEN 总被引:12,自引:3,他引:9
Satoh Kimihiko; Hatayama Ichiro; Tateoka Noboru; Tamai Katsuto; Shimizu Toshio; Tatematsu Masae; Ito Nobuyuki; Sato Kiyomi 《Carcinogenesis》1989,10(11):2107-2111
The single cells positive for placental glutathione S-transferase(GST-P), detectable in livers of rats soon after treatment withhepatocarcinogens, are possible initiated cells,the hypothesis tested in the present series of experiments.No low dose threshold was observed in male Sprague-Dawley ratsat different single doses of diethylnitrosamine (DEM) althougha plateau was reached between 160 and 200 mg/kg body weight.At the latter single dose 12 400 positive cells/cm3 were observedimmunohistochemically in rat livers after one week, the numbersthen decreasing to week 8 and thereafter rising again. In thenumbers then decreasing to week 8 and thereafter rising again.In the early stages single cells predominated but with timea gradual increase in mini-foci and larger lesions became evident.Application of selection pressure (feeding of diet containing0.02% 2-AAF plus partial hepatectomy) to rats 224 weeksafter single DEN-treatment resulted in the formation of largefoci positive for GST-P, especially in the early stages, thegrowth response being less pronounced with time. The numberof foci, on the other hand. was correlated with the number offoci, on the other hand, was correlated with the number ofsingle cells/mini-foci detected inhepatectomy tissue of thesame individuals. These results suggest that the early GST-Ppositive populations could be the precursor for preneoplasticfoci and nodules. 相似文献
98.
Yoshihiro Katagiri Kazuhide Mabuchi Tadanori Itakura Kohji Naora Kikuo Iwamoto Yoshimasa Nozu Shun-ichi Hirai Nobumasa Ikeda Toshio Kawai 《Cancer chemotherapy and pharmacology》1989,24(4):238-242
Summary Physicochemical properties of two types of adriamycin preparation, suspensions and emulsions prepared for i.a. chemotherapy of hepatocellular cacinoma, were investigated. A suspension was prepared by dispersing adriamycin directly into the lipid contrast medium, Lipiodol, whereas an emulsion was obtained by emulsifying an aqueous solution of adriamycin into Lipiodol. The dispersibility of the drug in each preparation was examined microscopically. The chemical stability of and drug release from the preparation were determined by high-performance liquid chromatography and spectrophotometry, respectively. The suspension was then given to ten patients with primary hepatocellular carcinoma. The suspension maintained good dispersibility without coagulation of drug particles, whereas coalescence of aqueous droplets and the resultant phase separation occurred 4 h after preparation of the emulsion. Both preparations maintained the initial drug content for at least 1 week at room temperature. The release of adriamycin was more prolonged in the suspension than in the emulsion. After i.a. administration of the suspension, a selective accumulation of Lipiodol in the tumor and decrease in serum -fetoprotein (AFP) levels were found in most patients. A significant amount of adriamycin was still detected in hepatic speciments resected from two patients 1 and 2 months after treatment. These findings suggest that the adriamycin-Lipiodol suspension may be a useful preparation for targeting chemotherapy to hepatocellular carcinoma. 相似文献
99.
N Iwai M Shibata F Mizoguchi H Nakamura M Katayama Y Taneda K Inokuma T Ozaki T Ichikawa S Matsui 《The Japanese journal of antibiotics》1989,42(12):2641-2660
Pharmacokinetic and clinical studies on cefmenoxime (CMX) in neonates and infants were conducted. 1. CMX 20 mg/kg was administered by intravenous bolus injection to 6 neonates (with ages 2 to 20 days) and 5 infants (with ages 36 to 107 days) and its serum concentration and urinary excretion rates were determined. In the neonates, serum concentrations of CMX after intravenous administration reached peak levels of 48.2 to 90.7 micrograms/ml (mean 70.4 +/- 14.3 micrograms/ml) in 1/4 hour, then declined with half-lives of 1.27 to 5.19 hours (mean 2.28 +/- 1.56 hours), and were 3.6 to 16.9 micrograms/ml (mean 8.3 +/- 6.0 micrograms/ml) at 6 hours. In the infants, serum concentrations at 1/4 hour were 67.5 to 111.0 micrograms/ml (mean 95.5 +/- 18.0 micrograms/ml); half-lives were 0.64 to 0.94 hour (mean 0.81 +/- 0.13 hour); and the serum concentrations at 6 hours were 0.2 to 1.1 micrograms/ml (mean 0.7 +/- 0.4 micrograms/ml). Mean peak serum concentrations in the neonates tended to be lower than those in the infants, but higher than those in children. Regarding the age differences of serum concentrations due to age in the neonates, their peak levels tended to be lower in younger ones. Half-lives were shorter in older subjects and, in early infancy, approached values observed in children. Urinary recovery rates in the first 6 hours after intravenous administration ranged from 43.6 to 87.5% (mean 61.6 +/- 14.6%) in the neonates and from 52.1 to 90.8% (mean 78.0 +/- 15.1%) in the infants. Thus, recovery rates were high even in younger subjects and tended to be higher in older subjects. 2. CMX was administered to 27 neonates and 4 infants to investigate its clinical effect, bacteriological effect and side effects. Clinical efficacy ratings of the drug in 19 neonate cases that could be evaluated (1 with purulent meningitis, 2 with suspected septicemia, 1 with acute bronchitis, 12 with acute pneumonia, 1 with impetigo, 1 with periumbilical abscess and 1 with acute pyelonephritis) were "excellent" in 14 cases, "good" in 4, and "poor" in 1. The efficacy rate covering "excellent" and "good" was 94.7%. In 4 infants (2 with acute pneumonia, 1 with periumbilical abscess and 1 with acute pyelonephritis), "excellent" was obtained in 2 cases and "good" in 2 cases. Thus, all the cases showed "good" or higher ratings. Bacteriologically, 1 strain of Staphylococcus aureus and 3 strains of Escherichia coli in neonates were eradicated while, in infants, 1 strain of S. aureus persisted but 1 of E. coli was eradicated.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
100.
Uchida Y Ohshima T Sasaki Y Suzuki H Yanai S Yamashita N Nakamura F Takei K Ihara Y Mikoshiba K Kolattukudy P Honnorat J Goshima Y 《Genes to cells : devoted to molecular & cellular mechanisms》2005,10(2):165-179
Collapsin response mediating protein-2 (CRMP2) has been identified as an intracellular protein mediating Semaphorin3A (Sema3A), a repulsive guidance molecule. In this study, we demonstrate that cyclin-dependent kinase 5 (Cdk5) and glycogen synthase kinase 3beta (GSK3beta) plays a critical role in Sema3A signalling. In In vitro kinase assay, Cdk5 phosphorylated CRMP2 at Ser522, while GSK3beta did not induce any phosphorylation of CRMP2. Phosphorylation by GSK3beta was exclusively observed in Cdk5-phosphorylated CRMP2, but barely in CRMP2T509A. These results indicate that Cdk5 primarily phosphorylates CRMP2 at Ser522 and GSK3beta secondarily phosphorylates at Thr509. The dual-phosphorylated CRMP2, but not non-phosphorylated or single-phosphorylated CRMP2, is recognized with the antibody 3F4, which is highly reactive with the neurofibrillary tangles of Alzheimer's disease. 3F4 recognized the CRMP2 in the wild-type but not cdk5-/- mouse embryonic brain lysates. The phosphorylation of CRMP2 at Ser522 caused reduction of its affinity to tubulin. In dorsal root ganglion neurones, Sema3A stimulation enhanced the levels of the phosphorylated form of CRMP2 detected by 3F4. Over-expression of CRMP2 mutant substituting either Ser522 or Thr509 to Ala attenuates Sema3A-induced growth cone collapse response. These results suggest that the sequential phosphorylation of CRMP is an important process of Sema3A signalling and the same mechanism may have some relevance to the pathological aggregation of the microtubule-associated proteins. 相似文献